{
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\begin{longtable}{l*{8}{c}}
\caption{Robust: Regressions Controlling for Frontier Experience.\label{tab:frontier}}\\
\hline\hline\endfirsthead\hline\endhead\hline\endfoot\endlastfoot
                &\multicolumn{4}{c}{OLS}                                                    &\multicolumn{4}{c}{2SLS}                                                   \\\cmidrule(lr){2-5}\cmidrule(lr){6-9}
                &\multicolumn{1}{c}{(1)}         &\multicolumn{1}{c}{(2)}         &\multicolumn{1}{c}{(3)}         &\multicolumn{1}{c}{(4)}         &\multicolumn{1}{c}{(5)}         &\multicolumn{1}{c}{(6)}         &\multicolumn{1}{c}{(7)}         &\multicolumn{1}{c}{(8)}         \\
                &War bonds         &Volunteers         &   Medals         &      PCA         &War bonds         &Volunteers         &   Medals         &      PCA         \\
\hline
Agricultural support&    0.159\sym{***}&    0.037\sym{***}&    0.014\sym{***}&    0.234\sym{***}&    0.353\sym{***}&    0.188\sym{***}&    0.052\sym{***}&    0.841\sym{***}\\
                &  [0.014]         &  [0.007]         &  [0.004]         &  [0.026]         &  [0.055]         &  [0.058]         &  [0.013]         &  [0.149]         \\
Frontier experience&   -0.015\sym{*}  &    0.002         &    0.002         &    0.003         &    0.010         &    0.020\sym{**} &    0.007\sym{***}&    0.076\sym{***}\\
                &  [0.007]         &  [0.004]         &  [0.002]         &  [0.014]         &  [0.012]         &  [0.009]         &  [0.002]         &  [0.026]         \\
WWI volunteering rate&   -0.005         &    0.110\sym{***}&    0.056\sym{***}&    0.450\sym{***}&   -0.007         &    0.102\sym{***}&    0.054\sym{***}&    0.420\sym{***}\\
                &  [0.035]         &  [0.026]         &  [0.021]         &  [0.117]         &  [0.043]         &  [0.035]         &  [0.020]         &  [0.139]         \\
WWI awards per capita&    0.191\sym{**} &    0.128         &    0.037         &    0.574\sym{**} &    0.171\sym{**} &    0.115         &    0.033         &    0.521\sym{*}  \\
                &  [0.078]         &  [0.100]         &  [0.034]         &  [0.268]         &  [0.085]         &  [0.092]         &  [0.040]         &  [0.280]         \\
log 1930 population&   -0.042\sym{***}&   -0.013         &   -0.017         &   -0.149\sym{**} &   -0.007         &    0.019         &   -0.010         &   -0.021         \\
                &  [0.016]         &  [0.011]         &  [0.013]         &  [0.070]         &  [0.022]         &  [0.020]         &  [0.014]         &  [0.081]         \\
1930 unemployment rate&   -0.384         &    0.610\sym{***}&    0.153         &    1.607\sym{*}  &   -0.119         &    0.743\sym{***}&    0.187         &    2.145\sym{*}  \\
                &  [0.262]         &  [0.205]         &  [0.155]         &  [0.888]         &  [0.310]         &  [0.285]         &  [0.161]         &  [1.121]         \\
Urban status: 1930&    0.053\sym{***}&    0.007         &    0.006         &    0.117\sym{***}&    0.021         &   -0.021         &   -0.001         &    0.005         \\
                &  [0.019]         &  [0.013]         &  [0.006]         &  [0.042]         &  [0.024]         &  [0.018]         &  [0.007]         &  [0.062]         \\
1930 farm share &   -0.424\sym{***}&   -0.087         &    0.027         &   -0.436\sym{**} &   -0.542\sym{***}&   -0.148\sym{*}  &    0.011         &   -0.682\sym{**} \\
                &  [0.079]         &  [0.055]         &  [0.026]         &  [0.181]         &  [0.123]         &  [0.076]         &  [0.029]         &  [0.300]         \\
1929 farm income&    0.055\sym{***}&   -0.028\sym{**} &    0.013         &    0.062         &    0.008         &   -0.072\sym{***}&    0.002         &   -0.115         \\
                &  [0.020]         &  [0.012]         &  [0.010]         &  [0.056]         &  [0.030]         &  [0.027]         &  [0.011]         &  [0.091]         \\
Mean Democratic vote share: 1898-1928&    0.002\sym{**} &   -0.000         &   -0.000         &    0.002         &   -0.000         &   -0.002\sym{**} &   -0.001         &   -0.006\sym{*}  \\
                &  [0.001]         &  [0.001]         &  [0.000]         &  [0.002]         &  [0.001]         &  [0.001]         &  [0.000]         &  [0.003]         \\
1930 share of men&   -1.657\sym{***}&   -1.260\sym{**} &   -0.542\sym{**} &   -6.457\sym{***}&   -1.466\sym{*}  &   -1.230\sym{**} &   -0.535\sym{**} &   -6.335\sym{***}\\
                &  [0.641]         &  [0.514]         &  [0.248]         &  [1.480]         &  [0.854]         &  [0.605]         &  [0.219]         &  [1.827]         \\
1930 share of blacks&   -0.290\sym{***}&   -0.430\sym{***}&   -0.046\sym{**} &   -1.171\sym{***}&   -0.197\sym{*}  &   -0.354\sym{***}&   -0.027         &   -0.862\sym{***}\\
                &  [0.086]         &  [0.039]         &  [0.022]         &  [0.147]         &  [0.117]         &  [0.066]         &  [0.025]         &  [0.240]         \\
1930 share of Japaneses&    5.506\sym{***}&    0.745         &    0.894         &   11.102         &    4.859\sym{*}  &    0.932         &    0.941         &   11.860\sym{*}  \\
                &  [1.951]         &  [1.237]         &  [1.323]         &  [6.971]         &  [2.542]         &  [1.584]         &  [1.222]         &  [6.319]         \\
1930 share of Germans&    0.614\sym{***}&   -0.712\sym{***}&    0.054         &   -0.067         &    0.461\sym{*}  &   -0.850\sym{***}&    0.020         &   -0.625         \\
                &  [0.172]         &  [0.152]         &  [0.123]         &  [0.676]         &  [0.238]         &  [0.187]         &  [0.128]         &  [0.779]         \\
1930 share of Italians&    0.113         &   -0.230         &   -0.005         &   -0.489         &    0.347         &   -0.036         &    0.044         &    0.294         \\
                &  [0.478]         &  [0.236]         &  [0.170]         &  [1.111]         &  [0.583]         &  [0.309]         &  [0.195]         &  [1.415]         \\
1930 share of veterans&    1.038\sym{***}&    1.115\sym{***}&    0.268\sym{**} &    3.891\sym{***}&    0.657\sym{*}  &    0.931\sym{***}&    0.222\sym{**} &    3.148\sym{***}\\
                &  [0.306]         &  [0.319]         &  [0.109]         &  [0.792]         &  [0.388]         &  [0.280]         &  [0.113]         &  [0.892]         \\
log 1939 average wage&    0.458\sym{***}&    0.211\sym{***}&    0.058\sym{***}&    1.040\sym{***}&    0.435\sym{***}&    0.189\sym{***}&    0.052\sym{**} &    0.951\sym{***}\\
                &  [0.055]         &  [0.033]         &  [0.020]         &  [0.128]         &  [0.069]         &  [0.045]         &  [0.022]         &  [0.170]         \\
WII war contract per capita&    0.279\sym{***}&   -0.034\sym{***}&    0.005         &    0.233\sym{***}&    0.282\sym{***}&   -0.034\sym{***}&    0.005         &    0.231\sym{***}\\
                &  [0.023]         &  [0.008]         &  [0.005]         &  [0.032]         &  [0.026]         &  [0.010]         &  [0.005]         &  [0.046]         \\
State FE (48)   &      Yes         &      Yes         &      Yes         &      Yes         &      Yes         &      Yes         &      Yes         &      Yes         \\
\hline
\(R^{2}\)       &    0.684         &    0.623         &    0.188         &    0.653         &    0.642         &    0.524         &    0.142         &    0.533         \\
Mean dependent variable&    4.659         &    0.634         &    0.140         &   -0.012         &    4.659         &    0.634         &    0.140         &   -0.012         \\
Rubin-Anderson test (p-value)&                  &                  &                  &                  &    0.000         &    0.009         &    0.000         &    0.000         \\
Observations    &     3020         &     2329         &     2329         &     2329         &     3020         &     2329         &     2329         &     2329         \\
\hline\hline
\end{longtable}
}
